1. Field of the Invention
The present invention relates to a digital modulation circuit which can be applied to a digital communication system, and more particularly, to a digital modulation circuit using a pulse, capable of reducing power consumption and being implemented in a simple structure.
2. Description of the Related Art
In general, wireless communication employs a modulation method of mixing a data signal (baseband signal) with a local oscillation signal in order to perform communication within a bandwidth determined as a standard. The modulation method is directly applied to an ultra-wideband communication using a pulse.
However, since the conventional modulation method of mixing the local oscillation signal uses a phase locked loop (PLL) circuit in order to fix a frequency of the local oscillating signal, there are problems in that a structure of a transmitter is complicated, and power consumption of the transmitter increases. In addition, when the conventional modulation method of mixing the local oscillation signal is employed, there is a problem in that a structure for synchronization acquisition of a carrier signal to implement a receiver having a synchronization scheme is very complicated.